Encrypt and decrypt text with AES-256-GCM and a passphrase. Runs entirely in your browser — neither the message nor the passphrase is ever transmitted.
First time here? Type or paste your message Your input is processed locally and disappears when you close the tab.
Sometimes a message needs to survive a channel you do not trust — a shared inbox, a chat log, a support ticket. This free aes encryption online tool encrypts text with a passphrase using AES-256-GCM, entirely inside your browser.\n\nThe key is derived from your passphrase with PBKDF2-SHA256 at 250,000 iterations, which makes brute-forcing a weak passphrase expensive rather than instant. Every message gets a fresh random salt and initialisation vector, so encrypting the same text twice produces completely different output — an important property, because identical ciphertext leaks the fact that two messages are the same.\n\nGCM is authenticated encryption, which means it detects tampering as well as protecting content. If a single byte of the ciphertext is altered in transit, decryption fails rather than producing corrupted text. It cannot tell you whether the passphrase was wrong or the data was modified, and deliberately so — distinguishing the two would hand an attacker useful information.\n\nEverything runs through the Web Crypto API in your browser. Nothing is uploaded, which is the only sane arrangement: a service that receives your plaintext in order to encrypt it has already seen the thing you were protecting. Pair it with the Passphrase Generator for something strong enough to be worth the algorithm behind it.
Type or paste your message
Enter a strong passphrase
Click Encrypt
Send the encrypted string, and the passphrase separately
AES-256-GCM with PBKDF2-SHA256, 250,000 iterations. A random salt and IV are generated per message, so encrypting the same text twice produces different output — which is what you want.
Send the passphrase over a different channel from the message. Emailing both together is the same as emailing plaintext.